Monolithic haptic touch screen, manufacturing method thereof, and display device including the same

• US 10,318,091 B2
• Filed: 12/11/2014
• Issued: 06/11/2019
• Est. Priority Date: 12/13/2013
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Lee, YongWoo, Ham, YongSu
• Primary Examiner(s): Lee, Nicholas J
• Assistant Examiner(s): Oliver, Gerald L
• Application Number:
  US14/568,029
• Publication Number:
  US 20150169118A1
• Time in Patent Office: 1,643 Days
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

A monolithic haptic-type touch screen capable of performing both touch recognition and haptic feedback are provided. The monolithic haptic-type touch screen includes an insulating film formed by doping ferroelectric material in an electroactive polymer (EAP), an upper electrode formed on an upper surface of the insulating film, and a lower electrode formed on a lower surface of the insulating film and corresponding to the upper electrode.

Claims

1. A monolithic haptic-type touch screen comprising:

an insulating film including doped ferroelectric material in an electroactive polymer (EAP);

an upper electrode disposed on an upper surface of the insulating film; and

a lower electrode disposed on a lower surface of the insulating film and corresponding to the upper electrode,

wherein the upper electrode and the lower electrode, responsive to a touch input on the monolithic haptic-type touch screen, generates a signal indicative of a location of the touch input on the monolithic haptic-type touch screen based on a change in capacitance between the lower electrode, the insulating film, and the upper electrode before and after the touch input, and

wherein the upper electrode and the lower electrode, responsive to receiving a vibration signal, generates a haptic output of vibrations by causing the insulating film to repeatedly contract and expand responsive to the vibration signal.

2. The monolithic haptic-type touch screen of claim 1, wherein the EAP is one selected from a group consisting of dielectric elastomers of silicon, acryl, and urethane.

3. The monolithic haptic-type touch screen of claim 1, wherein the ferroelectric material is one selected from a ceramic compound group consisting of barium titanate, lead titanate, lead zirconate, and niobium potassium oxide.

4. The monolithic haptic-type touch screen of claim 1, wherein a thickness of the insulating film ranges from 50 μ

m to 200 μ

m.

5. The monolithic haptic-type touch screen of claim 1, wherein the upper electrode and the lower electrode include one selected from a group consisting of carbon nanotube (CNT), an organic conductive polymer, graphene, silver nanowire, and metal mesh.

6. The monolithic haptic-type touch screen of claim 1, wherein the vibration signal comprises a voltage signal.

7. The monolithic haptic-type touch screen of claim 6, wherein the haptic output of vibrations is generated after a touch sensing operation.

8. The monolithic haptic-type touch screen of claim 1, wherein the signal indicative of the location of the touch input is provided to a touch controller.

9. A display device comprising:

a display panel configured to display an image;

a monolithic haptic-type touch screen disposed on the display panel and configured to recognize a user'"'"'s touch and provide a haptic feedback to the user, the monolithic haptic-type touch screen including;

an insulating film composed of doped ferroelectric material in an electroactive polymer (EAP),

an upper electrode disposed on an upper surface of the insulating film, and

a lower electrode disposed on a lower surface of the insulating film and corresponding to the upper electrode,

wherein the upper electrode and the lower electrode, responsive to the user'"'"'s touch, generates a signal indicative of a location of the user'"'"'s touch based on a change in capacitance between the lower electrode, the insulating film, and the upper electrode before and after the user'"'"'s touch, and

wherein the upper electrode and the lower electrode, responsive to receiving a vibration signal, generates a haptic output of vibrations by causing the insulating film to repeatedly contract and expand responsive to the vibration signal; and

a protective cover disposed on the monolithic haptic-type touch screen.

10. The display device of claim 9, wherein the protective cover includes transparent plastic of polymethacrylate or polycarbonate.

11. The display device of claim 9, further comprising:

an insulating sheet disposed between the monolithic haptic-type touch screen and the display panel.

12. The display device of claim 9, wherein the vibration signal comprises a voltage signal.

13. The display device of claim 12, wherein the haptic output of vibrations is generated after a touch sensing operation.

14. The display device of claim 9, wherein the signal indicative of the location of the touch input is provided to a touch controller.

15. A display device comprising:

a display panel configured to display an image; and

a haptic touch-sensitive structure including;

a first electrode disposed proximal to a user-facing side of the display device;

a second electrode disposed distal to the user-facing side of the device; and

an insulating film formed between the first electrode and the second electrode,

wherein the haptic touch-sensitive structure, responsive to a touch input on a monolithic haptic-type touch screen, is configured to generate a touch signal indicative of a location of the touch input on the monolithic haptic-type touch screen based on a change in capacitance between the first electrode, the insulating film, and the second electrode before and after the touch input, and

wherein the haptic touch-sensitive structure, responsive to applying a vibration signal to the first electrode and the second electrode, is further configured to generate a haptic output of vibrations by causing the insulating film to repeatedly contract and expand responsive to the vibration signal.

16. The display device of claim 15, wherein the haptic touch-sensitive structure is configured to generate the haptic output at the location of the touch input, responsive to the vibration signal including the location of the touch input applied to the first electrode and the second electrode.

17. The display device of claim 15, wherein the insulating film includes doped ferroelectric material in an electroactive polymer (EAP), and the vibration signal is a voltage signal applied to both the first electrode and the second electrode to generate the haptic output.

18. The display device of claim 17, wherein the insulating film is substantially transparent to visible light.

19. The display device of claim 17, wherein the EAP is one selected from a group consisting of dielectric elastomers of silicon, acryl, and urethane.

20. The display device of claim 17, wherein the ferroelectric material is one selected from a ceramic compound group consisting of barium titanate, lead titanate, lead zirconate, and niobium potassium oxide.

21. The display device of claim 17, wherein a thickness of the insulating film ranges from 50 μ

m to 200 μ

m.

22. The display device of claim 17, wherein the first electrode and the second electrode include one selected from a group consisting of carbon nanotube (CNT), an organic conductive polymer, graphene, silver nanowire, and metal mesh.

23. The display device of claim 15, wherein the vibration signal comprises a voltage signal.

24. The display device of claim 23, wherein the haptic output of vibrations is generated after a touch sensing operation.

25. The display device of claim 15, wherein the touch signal is generated by a touch controller.